In application Ser. No. 08/957,273, a sprayer tank or other pressure vessel is provided with an internal threaded boss that is designed to enhance the seal with a hose adapter as internal tank pressure increases. This hose adapter (i) is capable of swivel action independent of the tank fitting hose nut, (ii) that possesses pressure release slots and (iii) has the ability to remove the swivel part, supply tube and hose without removing the tank fitting hose nut.